3b53d3045b
MCA probing support for the new x86 setup code. This implements the same functionality as the assembly version. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
43 lines
949 B
C
43 lines
949 B
C
/* -*- linux-c -*- ------------------------------------------------------- *
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*
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* Copyright (C) 1991, 1992 Linus Torvalds
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* Copyright 2007 rPath, Inc. - All Rights Reserved
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*
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* This file is part of the Linux kernel, and is made available under
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* the terms of the GNU General Public License version 2.
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*
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* ----------------------------------------------------------------------- */
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/*
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* arch/i386/boot/mca.c
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*
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* Get the MCA system description table
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*/
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#include "boot.h"
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int query_mca(void)
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{
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u8 err;
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u16 es, bx, len;
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asm("pushw %%es ; "
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"int $0x15 ; "
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"setc %0 ; "
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"movw %%es, %1 ; "
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"popw %%es"
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: "=acdSDm" (err), "=acdSDm" (es), "=b" (bx)
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: "a" (0xc000));
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if (err)
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return -1; /* No MCA present */
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set_fs(es);
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len = rdfs16(bx);
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if (len > sizeof(boot_params.sys_desc_table))
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len = sizeof(boot_params.sys_desc_table);
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copy_from_fs(&boot_params.sys_desc_table, bx, len);
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return 0;
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}
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